python format 在sql中对 string 和 int 类型的变化

>>> s = '12345'
>>> q0 = "select nid from news_simhash where first_16={0}"
>>> q1 = "select nid from news_simhash where first_16='{0}'"
>>> from doc_process import get_postgredb_query
>>> conn, cursor = get_postgredb_query()
>>> cursor.execute(q0.format(s))  #出错
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
psycopg2.ProgrammingError: operator does not exist: text = integer
>>> conn2, cursor2 = get_postgredb_query()
>>> cursor2.execute(q1.format(s))  #正确执行

>>> q0.format(s)
'select nid from news_simhash where first_16=12345'
>>> q1.format(s)
"select nid from news_simhash where first_16='12345'"